Thiotepa-Induced Toxicity: A Clinical Mimic of Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis Featuring Severe Mucositis, Diffuse Dusky Discoloration, and Skin Sloughing.

Background: Thiotepa, an alkylating agent commonly used in chemotherapy, is increasingly recognized to induce cutaneous reactions resembling toxic erythema of chemotherapy (TEC). This condition is characterized by erythema, hyperpigmentation, and mucositis, often affecting intertriginous areas, and can mimic the early stages of Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN).

Case Description: A 31-year-old woman with a history of systemic lupus erythematosus, antiphospholipid antibody syndrome, seizures, and chronic kidney disease was admitted for the management of central nervous system (CNS) lymphoma.